Mixers for two liquids, such as those for supplying engines with a mixture of fuel and lubricant



y 1, 1960 c. CARBONERO 2,938,509

MIXERS FOR TWO LIQUIDS, SUCH AS THOSE FOR SUPPLYING ENGINES WITH A MIXTURE OF FUEL AND LUBRICANT Filed Jan. 5, 1959 2 Sheets-Sheet 1 n 2 Z 1 $8 Z9 Z9 5: 55-2- 3 31 18 30 56 E4 29 a; 22 9 j 23 K May 31, 1960 c. CARBONERO 2,938,509

MIXERS FOR TWO L IDS, SUCH AS THOSE FOR SUPPLYING GINES WITH IXTURE OF FUEL AND LUBRICANT 9 2 Sheets-Sheet 2 Filed Jan. 5,

United States Patent W MIXERS FOR TWO LIQUIDS, SUCH AS THOSE FOR SUPPLYLNG ENGINES WITH A MIXTURE OF FUEL AND LUBRICANT Carlo Carbonero, Paris, France, assignor to Society Ateliers de Construction de Motocycles et Automobiles, Paris, France, a society of France Filed Jan. 5, 1959, Ser. No. 784,925

Claims priority, application France Aug. 14, 1958 8 Claims. (Cl. 123-139) The invention relates to volumetric mixers for two liquids, particularly such as those for supplying internal combustion engines with a suitably measured mixture of fuel and lubricant, for example to the mixers for ensuring the supply of a mixture of gasoline and oil in a two-stroke engine for motor vehicles or any other applications.

Its main object is to render these apparatuses such that they meet the various desiderata in practice better than at present, and in particular so that they are more reliable in operation.

It consists, mainly, in constructing apparatus of the type in questionsubstantially from two pumps respectively supplying the two liquids in predetermined proportions with a view to mixing them, and actuated from one and the same control means (for example of the cam, crank or eccentric type) preferably driven by a driving shaft with the interposition of a reduction mechanism of the worm or gear type, in combination with means (particularly of the friction or other clutch type) adapted to permit the slowing down or interruption of the drive in relation to the required delivery.

Apparatus of the type in question may be provided with a diaphragm pump for the fuel and a piston pump for the lubricant, preferably both driven by a single control, which piston pump may, to advantage, be of a type comprising a rotary distributor with a working cylinder incorporated in said distributor.

Apparatus of the type in question may also be provided with automatic correcting means influenced by the pressure in the delivery pipe of the mixture, said means acting for example on the contact pressure of the clutch as mentioned above when such a clutch is provided; said means comprising in particular a diaphragm which is subject to the delivery pressure and adapted to release the clutch spring when said pressure increases.

Apparatus of the type in question may be adapted in such a manner that the two liquids are supplied, preferably separately, to a mixing chamber of a substantial capacity interposed between the pumps allocated to each liquid and the place where the mixture is used.

In apparatus of the type in question, the lubricant reservoir may be provided with means adapted to permit the cessation of operation when said reservoir becomes empty,

said means acting, for example, by means of a float to cut the ignition current to the engine.

Means may also be provided to warn, for example,

Figures 2 to 4 show respectively in vertical section 9 and in cross sections along III- 111 and IV-IV of Figure 2, a second embodiment of the said mixer.

If it is intended, for example, to produce a mixing apparatus adapted to supply a two-stroke engine, for example a carburetor included in the latter or any other alternative device, with a mixture of gasoline and oil in suitable proportions, from two reservoirs containing said liquids, the procedure may be as follows.

Said apparatus consists essentially of two pumps, one for the gasoline, the other for the oil, which pumps are actuated from one and the same control connected to the engine shaft, in combination with means to permit the drive to be slowed down or stopped as a function of the requirements of the engine, said means preferably consisting of a friction clutch device (although any others which temporarily cut off or slow down the drive may be considered).

In order to meet the above conditions, first as regards the pumps themselves, recourse is preferably had to another feature of the invention according to which there is used: for the gasolinea diaphragm pump; and for the oil-a piston pump, both being controlled from one and the same shaft, as indicated above, and with a reduction device ensuring a satisfactory reduction, in such a manner as to ensure that said pumps are of suitable dimensions (that is to say not too small).

This difierent construction for the two pumps takes into consideration difierences in viscosity as well as the differences in volume which can be mixed per cycle, of the gasoline and oil respectively. Actually, a piston pump for the gasoline would involve considerable difficulties in construction as regards behaviour and vice versa, a diaphragm pump for the oil could not ensure a precise measurement of the small volume displaced, primarily because of the presence of the various valves.

A first embodiment of the invention, illustrated in Figure 1, will first be described by way of example.

According to this embodiment, the gasoline pump comprises a casing 1 fixed to the housing 2 of the mixer, the diaphragm 3 of said pump being adapted to draw in the gasoline which arrives through a valve 4- situated at the mouth of a pipe 5 bringing the gasoline from a tank 6, to deliver it through another valve 7 into a pipe 8 (which may be housed partially in the wall of the housing 2).

As for the oil pump, this comprises a piston 9 displaceable in a bore 10 and distributor means which may conveniently consist of a simple port 11 supplied at 12 from a receptacle 13 containing the oil, which port, on the one hand, effects the admission when it is uncovered by the piston and, on the other hand, permits the delivery when it is covered by the piston. The evacuation of the oil then takes place through a valve 14 with a spring 15, leading into a mixing chamber 16 into which the gasoline pipe 8 likewise leads, said chamber 16 being connected by a pipe 17 to the carburettor.

It is understood that the proportion of oil could be rendered variable by any suitable means acting on the delivery of the gasoline pump or on the delivery of the oil pump. For example, the relative position of the port 11 could'be rendered adjustable for this purpose.

In order to drive the active members (diaphragm 3 and piston 9) of the two pumps thus constructed, recourse may be had, for example, to a control member such as a cam 18 mounted on a shaft 19 preferably arranged between the said active members, the diaphragm 3 being controlled by the cam 18 by means of links 20 or the like, while the piston 9 is itself controlled by a link 21 or the like.

By causing said cam 18 to rotatewith the aid of driving means which will be discussed more specifically belowgasoline and oil are therefore supplied jointly to the mixing chamber 16 under conditions such that the volume of gasoline supplied to'said chamber depends on the displacement of the diaphragm 3, which displacement is a function of the dimensions of the cam 18, and, in turn, the volume of oil measured out by the corresponding pumpin each cycle is a function of the position, ofthe port 11 in relation to the piston 9.

. As regards the oil pump, it should be noted that the stroke of the piston 9 is made substantially longer than that necessary for delivery, in order to permitregulation of the admission port and to provide the oil with an opportunity of flowing into'the cylinder of the. pump. The excess oil drawn in is forced to flow back into the admission pipe so long as the piston 9 has not completely blocked the portion 11; once this blocking is efiected, the 7 pressure can rise until it overcomes .the reaction of the spring 15 of the delivery valve 14. i

Now as regards the means for driving the shaft 19 and its cam 18 from a shaft such as 22 connected to the engine, these comprise on the one hand a reduction gear,

ing said clutch. Although numerous other solutions are possible for the arrangement of this clutch, one of the two discs, 26, for example may be rigidly connected to the shaft 19 while the other 25 slides axially on said shaft. The spring 27 is then interposed between two parts or plates 28, 29, one of which, 28, is rigidly connected to the shaft 19 while the other, 29, is connected to the plate 25 by a rod 30 inside the shaft 19, and a cotter 31.

In the manner which has just been-described, and as a result of the clutch, an assembly is obtained which enables the capacity of the mixer to be adapted in proportion to the quantity of fuel mixture required by the engine and the pressure in the delivery pipe, and consequently the .level of the carburetor chamber, to be prevented. from rising to such values that they would prejudice the operation of the carburetor.

The spring 27 is therefore calibrated in such-a manner (if necessary in an adjustable manner) that the clutch can slip in accordance with a predetermined torque. The

slipping is inversely proportional to the fuel requirements. 7 r

If, in principle, a mixer of this type meets the conditions found in practice, allowance must also be made, at least in certain cases, for possible variations in the coefiicient of friction of the clutch, through wear of the contact surfaces and variation in the viscosity of the oil or grease in the clutch casing. Excessive variations might result in the delivery pressure and in the level of the carburetor chamber, leading to excessive fuel consumption.

-In order to reduce or ofliset such variations, it is an advantage to add to an assembly of the type specified above, an automatic correction device acting as a function of the delivery pressure of the mixture, for example, in such a manner as to cause the contact pressure of the clutch to vary in the inverse direction. In this manner, it is possible to maintain the slipping torque almost constant and thus to avoid excessive variations in the'delivery pressure.

Thus said corrector device may consist of a resilient diaphragm such as 32, mounted in a casing and subjected,

. on one of its faces at 33, to the delivery pressure, through a pipe 34 connecting the chamber 33 to the delivery pipe 17. At the other face, the diaphragm 32 bears against the plate 29 in such a manner that an increase in the delivery pressure of the mixture tends to release the spring 27 and at the same time the clutch.

It is also possible, inorder to icompletethe assembly, to have recourse to the following additional features which may, if necessary, be used separately.

According to one'of these features, the oil reservoir comprises means adapted to interrupt automatically the operation of the engine when the supply of oil in said reservoir is exhausted. f i

Thus, according to one of the conceivable embodiments, provision is made for said means to cut the ignition circuit to the engine when said reservoir is empty. 7

In Figure 1, it is assumed that a float 35 which is suitably guided and capable, in its lower position, of cutting off the ignition circuit of said engine, through the action of contactssuch as 36, is provided in the reservoir 13. These contacts 36 may, for example, be carried by a guide. slide 37. Actually, the interruption of the ignition circuit would take place by grounding said circuit.

According to a similar arrangement, means may likewise be provided to permit a signal to'be lit when the level reaches a danger level in the reservoir such as 13. Figure 1 illustrates very diagrammatically,'at 38, a second float, the object of which is to bring into action a second set of contacts 39 efiecting the lighting of the telltale lamp. 7 7

The contacts 36, 39 are illustrated very diagrammatically in the drawings, it being understood that it is possible for any technician to construct them in a suitable manner.

A second embodiment of the invention will now be described with reference to Figures 2 to 4, comprising the application of certain additional arrangements which will be described below,,the members which are common to the two forms of construction not needing to be described again and bearing thesame reference numerals 10. Figures 2 to 4 as in Figure 1.

As regards the oil pump which is to draw and deliver oil originating from the tank 13 through the pipe 12,

, this is constructed in such a manner that it is of the type comprising a rotary distributor with a working cylinder incorporated in said distributor, for which reason, it 1s an advantage to provide in the driving shaft 19, a cylinder 40, orientated radially, in which reciprocates a piston 41 connected by its outer end, at 42, to a rotating ring 43 pivotally mounted in the body 2 of the apparatus, said ring being eccentric in relation to said driving shaft 19 in such a manner that when the latter rotates, the piston 41 is obliged to effect a reciprocating movement'in the cylinder 40 and also toprovide, towardsthe inner end of the cylinder 40, a distribution passage 44 which, in the course of one complete revolution of the shaft 19, passes successively opposite, first the outlet of the'pipe 12'bringing the oil from the tank 13, then themouth of an evacuation pipe 45 through which the oil which is delivered reaches a mixing chamberfwhich will be discussed in 'more detail below. V

.It should be noted that the amount of oil delivered on each revolution depends, among other factors, on the degree of eccentricity of the ring 43 in relation to the shaft 19, and this degree of eccentricity may, necessary, be made variable. I

Another original feature of the embodiment forming the subject of Figures 2 to 4 lies in the driving mechanism 'for the shaft 19, which mechanism consists of pairs of cylindrical gears 46, 47, 48, 49 coupling the shaft 22 of the engine to the wheel 24 which is mountedloose on the shaft 19 and withwhich'the plates 25 and 26 of the clutch cooperate as in the case of the first embodiment action therein, the speed of displacement of. theirmoving parts then being low which represents an additional advantage. Finally, as regards the mixture of gasoline and oil, ae-

cording to this second embodiment this is no longer effected in a simple chamber 16 of limited capacity but in a mixing chamber 59 of substantial capacity, to the top of which lead the delivery pipes 8 and 45 respectively from the gasoline pump and the oil pump.

With such a mixing chamber 50 of substantial capacity, it is possible to dispense with the diaphragm device 32 provided in the first embodiment, to correct the load of the spring 27 or" the clutch in the event of variations in the coefiicient of friction of said clutch.

Actually, if the capacity of said mixing chamber 50 is sufiicient, the variations in level in said chamber, due to variations in the coetncient of friction of the clutch, will be practically negligible.

Moreover, as a result of the independent intakes of the two liquids into the mixing chamber 50 there is no risk, in the event of imperfect closure of the valves, of a transfer of liquid from one tank to the other, which would have the annoying etfect of spoiling the ratio of the mixture.

It should be noted that the spring 27 of the clutch is designed in such a manner that said clutch slips beyond a predetermined torque, in relation to the mean level in the mixing chamber 50 in which there may then be provided, in order to control the gasoline intake, a floatspindle 51 such as those currently used for carburettors, the slipping of the clutch then being inversely proportional to be demand for mixture coming from the utilizing apparatus, though preferably without its being possible for said slip to be reduced to zero even when the demand in question is at its maximum, so that there is still a margin of adjustment in this extreme case.

As a result of which, whatever the form of construction adopted, it is possible to provide a mixing unit for oil and gasoline, the operation of which is sufiiciently clear from the above for it to be unnecessary to give any further explanations on the subject and which, in comparison with the existing units of the type in question, has numerous advantages, particularly that of permitting the oil and the gasoline to be measured out in a suitable manner, that of permitting excessive pressures to be avoided in the delivery pipe for the mixture, and that of ensuring every reliability in operation.

In a general manner, while I have, in the above description, disclosed what I deem to be practical and eificient embodiment of my invention, it should be well understood that I do not wish to be limited thereto as there might be changes made in the arrangement, disposition and form of the parts without departing from the principle of the present invention as comprehended within the scope of the accompanying claims.

What is claimed is:

1. For use in connection with an internal combustion engine, an apparatus for mixing together liquid fuel for operating said engine and a liquid lubricant to be added to said fuel, said fuel and said lubricant being supplied from two separate tanks, which apparatus comprises, in combination, a diaphragm pump fed with fuel from the fuel tank, a piston pump fed with lubricant from the lubricant tank, a mixing chamber, a pipe leading from the delivery of each of said pumps respectively to said chamber, a shaft operatively connected with both of said pumps for actuating them, driving means, and a friction clutch interposed between said driving means and said shaft.

2. An apparatus according to claim 1, in which said piston pump includes a cylinder mounted to rotate together with said shaft, a piston slidable in said cylinder, means operatively connected with said shaft for reciprocating said piston in said cylinder, and means operative by said shaft for connecting said cylinder alternately with said tank and with the pipe leading from the delivery of said fuel pump.

3. An apparatus according to claim 1, in which said shaft is provided with a cylindrical bore at right angles to the axis of said shaft so as to constitute a pump cylinder, a piston slidable in said cylinder, a ring freely rotatable about an axis parallel to said first mentioned aXis and distant therefrom, the outer end of said piston being pivotally connected with a point of said ring about an axis parallel to said two first mentioned axes, and means operative by said shaft for connecting said cylinder alternately with said tank and with the pipe leading from the delivery of said fuel pump.

4. An apparatus according to claim 1, including speed reducing means between said driving means and said clutch.

5. An apparatus according to claim 1 further including automatic means responsive to the pressure of the liquid delivered by said mixing chamber for adjusting friction clutch.

6. An apparatus according to claim 5, in which said clutch includes at least two elements in slipping contact with each other and a spring mounted to apply said elements against each other to prevent slipping as long as the torque transmitted by said clutch is below a given value, said automatic means being adapted to vary the load of said spring.

7. A mixer according to claim 1 further including means responsive to variation of the liquid level in the lubricant tank for stopping said engine when said level drops to the position where said lubricant tank is empty.

8. A mixer according to claim 1, further including means responsive to variation of the liquid level in the lubricant tank for giving a signal when said level drops to a predetermined position.

Gentzen Feb. 19, 1929 Hilton Dec. 23, 1958 

